Secondary battery with hydroxide-ion-conducting ceramic separator

The present invention provides a secondary battery with a hydroxide-ion-conducting ceramic separator. This secondary battery comprises a positive electrode, a negative electrode, an alkaline electrolyte, a ceramic separator that separates the positive electrode and the negative electrode and that is made of an inorganic solid electrolytic body having hydroxide-ion conductivity, a porous substrate provided on at least one side of the ceramic separator, and a container for containing at least the negative electrode and the alkaline electrolyte, wherein the inorganic solid electrolytic body is in the form of a film or layer that is densified to a degree such that the inorganic solid electrolytic body does not have water permeability and wherein the thickness of the porous substrate is 100-1800 µm. With the secondary battery according to the present invention, a decrease in the energy density and an increase in the internal resistance can be advantageously inhibited, while realizing a low resistance by way of forming the ceramic separator as a thin film without the risk of a decrease in strength.